Heat a dash of oil in a large frying pan, and add the sliced leek. Cook for a few minutes over a medium heat, until just soft, then add the sliced mushrooms. If you can't fit them all in the pan in one go, add them a handful at a time (they'll reduce in volume as they cook), or split them into two separate pans. Add the garlic and a generous pinch of black pepper, and cook for a few more minutes until the leek and mushrooms are all cooked thoroughly and just beginning to brown.

Transfer the cooked vegetables to a blender (you can hold back a few mushrooms to use for garnish if desired).

To deglaze the pan, add a little of the vegetable stock to the empty frying pan, and bring to a boil. Scrape any cooked-on bits of mushroom and leek from the bottom of the pan (make sure you don't use a metal spatula if your pan is non-stick), into the liquid.

Add the liquid from the pan to the blender, along with the remaining veggie stock, silken tofu, and parsley (I actually used semi-dried parsley). Seal the blender with the lid, and blitz thoroughly until the soup is smooth.

Check the soup's seasoning, adding more salt, pepper or parsley if desired, and blitzing again to combine.

To make the toasted pine nuts, add the nuts to a dry frying pan, and cook over a medium heat for a couple of minutes. Once the pan is hot, the nuts will brown very quickly, so keep stirring them, and remove them from the pan as soon as they're browned to your liking.

Serve the vegan cream of mushroom soup topped with any remaining garlic mushrooms, the toasted pine nuts, and some extra parsley.